An inference question tests what you can conclude from a text that brings different sources together. Read the words around the blank to see what the conclusion must address, then put each source and finding in a few words. Ask what the findings show together and what they leave unknown. Predict a limited conclusion the clues support, so your answer doesn’t add claims the text doesn’t support. Wrong choices can go past the evidence even when they reuse the passage’s own words.
Hints
- Hint 1
Read the last sentence up to the blank. What are the researchers drawing a conclusion about?
- Hint 2
Check what each source records. What does the passage say about the ship logs and the underwater microphones?
- Hint 3
Link the route shifts to the krill blooms and ocean currents. What does that link help researchers understand about whale migration?
Step-by-step
Combine the clues and limit the prediction
Step 1Find what is being combined
The last sentence centers on integrating these historical and modern data sets, so the blank needs a conclusion about using both records together. What does each source add? The nineteenth- and twentieth-century ship logs describe earlier seasonal sightings, while the microphones supply modern sound recordings, giving researchers past and recent evidence to compare.
- Step 2
Connect the route shifts to their cause
Preliminary comparisons reveal that whales shifted their routes to follow new deep-water krill blooms produced by changing ocean currents. What do those clues add up to? The comparisons help explain why the whales’ routes changed, not only where whales were found. Let's keep our prediction limited: the combined records help researchers judge how migration responds when ocean conditions change. Since these are early findings, that useful link isn't a fixed rule for all migrations.
- Step 3
Reject claims beyond the findings
What would go past these clues? The phrase over the past 15 years tells us how long the shifts were observed, not whether they repeat in predictable 15-year cycles. The words already stabilized add a stopping point that the passage never reports. And can replace ship logs conflicts with augmented those records, which means adding modern data to the logs rather than discarding them.
- Step 4
Draw the limited conclusion
How could that understanding help with later migrations? Combining the historical and modern data sets gives scientists both a longer record and recent tracking to draw on, rather than limiting them to one source. The choice with may allow says this fuller evidence could improve migration predictions, without guaranteeing accurate forecasts. Choice D.